Abstract: A system for encapsulating a cable 12 for the purpose of splice closures, breakout closures, jacket repair closures or end capping, in which a casing is fitted around a part of the cable to be sealed, defining within it a cavity surrounding the cable, and a sealant material in the form of a two part acrylic structural adhesive material is injected to fill the cavity and cured in situ. The two part adhesive has a base resin including a methacrylate monomer and a minor part including an oligomeric synthetic rubber and a curative for the monomer, preferably an organoborane accelerator such as an organoborane amine complex, which may be carried by a polyfunctional aziridine. The two parts are preferably mixed at a volume ratio of 2:1 to 15:1.